any positives with using the 4 beam array, 2 on each side, and 4 torpedo tubes, 2 on each side?

I have never seen anyone advocate using 2 torps per side on a cruiser. I believe it's a combination of the the low turning speed, the shared global cooldown, and the fact that torpedoes are naturally mutually exclusive with broadsides.

If you're using torpedoes, a single Quantum torpedo means you need to reacquire the target every 8.5 seconds but a pair would mean you need to reacquire 3 seconds after firing the first, to get the most out of it.